A novel nanobody broadly neutralizes SARS-CoV-2 via induction of spike trimer dimers conformation.

The ongoing mutations of the SARS-CoV-2 pose serious challenges to the efficacy of the available antiviral drugs, and new drugs with fantastic efficacy are always deserved investigation. Here, a nanobody called IBT-CoV144 is reported, which exhibits broad neutralizing activity against SARS-CoV-2 by inducing the conformation of spike trimer dimers. IBT-CoV144 was isolated from an immunized alpaca using the RBD of wild-type SARS-CoV-2, and it showed strong cross-reactive binding and neutralizing potency against diverse SARS-CoV-2 variants, including Omicron subvariants. Moreover, the prophylactically and therapeutically intranasal administration of IBT-CoV144 confers fantastic protective efficacy against the challenge of Omicron BA.1 variant in BALB/c mice model. The structure analysis of the complex between spike (S) protein, conducted using Cryo-EM, revealed a special conformation known as the trimer dimers. This conformation is formed by two trimers, with six RBDs in the "up" state and bound by six VHHs. IBT-CoV144 binds to the lateral region of the RBD on the S protein, facilitating the aggregation of S proteins. This aggregation results in steric hindrance, which disrupts the recognition of the virus by ACE2 on host cells. The discovery of IBT-CoV144 will provide valuable insights for the development of advanced therapeutics and the design of next-generation vaccines.

Repeated Omicron infection dampens immune imprinting from previous vaccination and induces broad neutralizing antibodies against Omicron sub-variants.

OBJECTIVE: Similar with influenza virus, antigenic drift is highly relevant to SARS-CoV-2 evolution, and immune imprinting has been found to limit the performance of updated vaccines based on the emerging variants of SARS-CoV-2. We aimed to investigate whether repeated exposure to Omicron variant could reduce the immune imprinting from previous vaccination. METHODS: A total of 194 participants with different status of vaccination (unvaccinated, regular vaccination and booster vaccination) confirmed for first infection and re-infection with BA.5, BF.7 and XBB variants were enrolled, and the neutralizing profiles against wild type (WT) SARS-CoV-2 and Omicron sub-variants were analyzed. RESULTS: Neutralizing potency against the corresponding infected variant is significantly hampered along with the doses of vaccination during first infection. However, for the participants with first infection of BA.5/BF.7 variants and re-infection of XBB variant, immune imprinting was obviously alleviated, indicated as significantly increased ratio of the corresponding infected variant/WT ID50 titers and higher percentage of samples with high neutralizing activities (ID50 > 500) against BA.5, BF.7 and XBB variants. Moreover, repeated Omicron infection could induce strong neutralizing potency with broad neutralizing profiles against a series of other Omicron sub-variants, both in the vaccine naive and vaccine experienced individuals. CONCLUSIONS: Our results demonstrate that repeated Omicron infection dampens immune imprinting from vaccination with WT SARS-CoV-2 and induces broad neutralizing profiles against Omicron sub-variants.

Potential COVID-19 remedies from repurposed drugs and herbal small RNAs.

To date, SARS-CoV-2 has caused millions of deaths, but the choice of treatment is limited. We previously established a platform for identifying Food and Drug Administration (FDA)-approved repurposed drugs for avian influenza A virus infections that could be used for coronavirus disease 2019 (COVID-19) treatment. In this study, we analyzed blood samples from two cohorts of 63 COVID-19 patients, including 19 patients with severe disease. Among the 39 FDA-approved drugs we identified for COVID-19 therapy in both cohorts, 23 drugs were confirmed by literature mining data, including 14 drugs already under COVID-19 clinical trials and 9 drugs reported for COVID-19 treatments, suggesting the remaining 16 FDA-approved drugs may be candidates for COVID-19 therapy. Additionally, we previously reported that herbal small RNAs (sRNAs) could be effective components in traditional Chinese medicine (TCM) for treating COVID-19. Based on the abundance of sRNAs, we screened the 245 TCMs in the Bencao (herbal) sRNA Atlas that we had previously established, and we found that the top 12 TCMs for COVID-19 treatment was consistent across both cohorts. We validated the efficiency of the top 30 sRNAs from each of the top 3 TCMs for COVID-19 treatment in poly(I:C)-stimulated human non-small cell lung cancer cells (A549 cells). In conclusion, our study recommends potential COVID-19 remedies using FDA-approved repurposed drugs and herbal sRNAs from TCMs.

Analysis of binding and authentic virus-neutralizing activities of immune sera induced by various monkeypox virus antigens.

Monkeypox cases continue to increase globally, and there is an urgent need to develop a highly effective vaccine against monkeypox. This study investigated the binding and authentic-virus neutralizing activities of sera from mice immunized with EEV (extracellularly enveloped viruses) antigens B6R and A35R, and IMV (intrinsic material viruses) antigens M1R, A29L, E8L, and H3L against monkeypox virus. The results showed that immunizations of A35R and E8L could only induce lower titers of binding antibodies, in contrast, immunization of M1R induced the highest titers of binding antibodies, while immunization of B6R, H3L, and A29L induced moderate titers of binding antibodies. For the live monkeypox virus neutralization assay, the results showed that immunization with two doses of EEV antigen B6R did not effectively induce humoral immune responses to neutralize monkeypox live virus, immunization with EEV-A35R only induced weak monkeypox-neutralizing antibodies. In contrast, the immunization of the four types of monkeypox virus IMV antigens can all induce neutralizing antibodies against authentic monkeypox virus, among them, A29L and H3L induced the highest neutralizing antibody titers. The results of this study provide important references for the selection of antigens in the development of the next generation of monkeypox vaccines.

The dynamic molecular characteristics of neutrophils are associated with disease progression in dengue patients.

Dengue, the most prevalent mosquito-borne disease worldwide, poses a significant health burden. This study integrates clinical data and transcriptomic datasets from different phases of dengue to investigate distinctive and shared cellular and molecular features. Clinical data from 29 dengue patients were collected and analyzed alongside a public transcriptomic data set (GSE28405) to perform differential gene expression analysis, functional enrichment, immune landscape assessment, and development of machine learning model. Neutropenia was observed in 54.79% of dengue patients, particularly during the defervescence phase (65.79%) in clinical cohorts. Bioinformatics analyses corroborated a significant reduction in neutrophil immune infiltration in dengue patients. Receiver operating characteristic curve analysis demonstrated that dynamic changes in neutrophil infiltration levels could predict disease progression, especially during the defervescence phase, with the area under the curve of 0.96. Three neutrophil-associated biomarkers-DHRS12, Transforming growth factor alpha, and ZDHHC19-were identified as promising for diagnosing and predicting dengue progression. In addition, the activation of neutrophil extracellular traps was significantly enhanced and linked to FcγR-mediated signaling pathways and Toll-like receptor signaling pathways. Neutrophil activation and depletion play a critical role in dengue's immune response. The identified biomarkers and their associated pathways offer potential for improved diagnosis and understanding of dengue pathogenesis and progression.

Transcriptome dynamics of the BHK21 cell line in response to human coronavirus OC43 infection.

The progress of viral infection involves numerous transcriptional regulatory events. The identification of the newly synthesized transcripts helps us to understand the replication mechanisms and pathogenesis of the virus. Here, we utilized a time-resolved technique called metabolic RNA labeling approach called thiol(SH)-linked alkylation for the metabolic sequencing of RNA (SLAM-seq) to differentially elucidate the levels of steady-state and newly synthesized RNAs of BHK21 cell line in response to human coronavirus OC43 (HCoV-OC43) infection. Our results showed that the Wnt/ß-catenin signaling pathway was significantly enriched with the newly synthesized transcripts of BHK21 cell line in response to HCoV-OC43 infection. Moreover, inhibition of the Wnt pathway promoted viral replication in the early stage of infection, but inhibited it in the later stage of infection. Furthermore, remdesivir inhibits the upregulation of the Wnt/ß-catenin signaling pathway induced by early infection with HCoV-OC43. Collectively, our study showed the diverse roles of Wnt/ß-catenin pathway at different stages of HCoV-OC43 infection, suggesting a potential target for the antiviral treatment. In addition, although infection with HCoV-OC43 induces cytopathic effects in BHK21 cells, inhibiting apoptosis does not affect the intracellular replication of the virus. Monitoring newly synthesized RNA based on such time-resolved approach is a highly promising method for studying the mechanism of viral infections.

Longitudinal viral shedding and antibody response characteristics of men with acute infection of monkeypox virus: a prospective cohort study.

Understanding of infection dynamics is important for public health measures against monkeypox virus (MPXV) infection. Herein, samples from multiple body sites and environmental fomites of 77 acute MPXV infections (HIV co-infection: N = 42) were collected every two to three days and used for detection of MPXV DNA, surface protein specific antibodies and neutralizing titers. Skin lesions show 100% positivity rate of MPXV DNA, followed by rectum (88.16%), saliva (83.78%) and oropharynx (78.95%). Positivity rate of oropharynx decreases rapidly after 7 days post symptom onset (d.p.o), while the rectum and saliva maintain a positivity rate similar to skin lesions. Viral dynamics are similar among skin lesions, saliva and oropharynx, with a peak at about 6 d.p.o. In contrast, viral levels in the rectum peak at the beginning of symptom onset and decrease rapidly thereafter. 52.66% of environmental fomite swabs are positive for MPXV DNA, with highest positivity rate (69.89%) from air-conditioning air outlets. High seropositivity against A29L (100%) and H3L (94.74%) are detected, while a correlation between IgG endpoint titers and neutralizing titers is only found for A29L. Most indexes are similar between HIV and Non-HIV participants, while HIV and rectitis are associated with higher viral loads in rectum.

Invigorating human MSCs for transplantation therapy via Nrf2/DKK1 co-stimulation in an acute-on-chronic liver failure mouse model.

Background: Since boosting stem cell resilience in stressful environments is critical for the therapeutic efficacy of stem cell-based transplantations in liver disease, this study aimed to establish the efficacy of a transient plasmid-based preconditioning strategy for boosting the capability of mesenchymal stromal cells (MSCs) for anti-inflammation/antioxidant defenses and paracrine actions in recipient hepatocytes. Methods: Human adipose mesenchymal stem cells (hADMSCs) were subjected to transfer, either with or without the nuclear factor erythroid 2-related factor 2 (Nrf2)/Dickkopf1 (DKK1) genes, followed by exposure to TNF-α/H2O2. Mouse models were subjected to acute chronic liver failure (ACLF) and subsequently injected with either transfected or untransfected MSCs. These hADMSCs and ACLF mouse models were used to investigate the interaction between Nrf2/DKK1 and the hepatocyte receptor cytoskeleton-associated protein 4 (CKAP4). Results: Activation of Nrf2 and DKK1 enhanced the anti-stress capacity of MSCs in vitro. In a murine model of ACLF, transient co-overexpression of Nrf2 and DKK1 via plasmid transfection improved MSC resilience against inflammatory and oxidative assaults, boosted MSC transplantation efficacy, and promoted recipient liver regeneration due to a shift from the activation of the anti-regenerative IFN-γ/STAT1 pathway to the pro-regenerative IL-6/STAT3 pathway in the liver. Importantly, the therapeutic benefits of MSC transplantation were nullified when the receptor CKAP4, which interacts with DKK1, was specifically removed from recipient hepatocytes. However, the removal of the another receptor low-density lipoprotein receptor-related protein 6 (LRP6) had no impact on the effectiveness of MSC transplantation. Moreover, in long-term observations, no tumorigenicity was detected in mice following transplantation of transiently preconditioned MSCs. Conclusions: Co-stimulation with Nrf2/DKK1 safely improved the efficacy of human MSC-based therapies in murine models of ACLF through CKAP4-dependent paracrine mechanisms.

Cytokine IL-5 and HGF: combined prediction of non-/low immune response to hepatitis B vaccination at birth in infants born to HBsAg-positive mothers.

Background: The immune response to hepatitis B vaccine may be influenced by numerous factors, and patients with non/low response re-exposed to hepatitis B virus remain susceptible. Thus, a better understanding of the underlying mechanisms of non/low immune response in infants born to Hepatitis B surface antigen (HBsAg)-positive mothers is essential. Methods: 100 infants born to HBsAg-positive mothers from 2015 to 2020 were enrolled in the study, further divided into the non/low response group (n=13) and the moderate strong response group (n=87) based on the quantification of hepatitis B surface antibody at 12 months of age. The differential expression of 48 immune-related cytokines in the two groups was compared and analyzed in detail. The key cytokines were further identified and clinically predictive models were developed. Results: We found that 13 cytokines were lowly expressed and one cytokine was highly expressed in the non/low response group, compared with the moderate strong response group at birth. In addition, 9 cytokines were lowly expressed and one cytokine was highly expressed in the non/low response group at 12 months of age. Furthermore, we found that IL-5 and HGF were promising predictors for predicting the immunization response to hepatitis B vaccine in infants, and the combination of the two cytokines showed the best predictive efficiency, with an area under the curve (AUC) value of 0.844. Conclusion: The present study provides a theoretical basis on cytokines for developing and implementing effective immunotherapies against non/low immune response in infants born to HBsAg-positive mothers.

Evolving immune evasion and transmissibility of SARS-CoV-2: The emergence of JN.1 variant and its global impact.

The continuous evolution of SARS-CoV-2 variants constitutes a significant impediment to the public health. The World Health Organization (WHO) has designated the SARS-CoV-2 variant JN.1, which has evolved from its progenitor BA.2.86, as a Variant of Interest (VOI) in light of its enhanced immune evasion and transmissibility. The proliferating dissemination of JN.1 globally accentuates its competitive superiority and the potential to instigate fresh surges of infection, notably among cohorts previously infected by antecedent variants. Notably, prevailing evidence does not corroborate an increase in pathogenicity associated with JN.1, and antiviral agents retain their antiviral activity against both BA.2.86 and JN.1. The sustained effectiveness of antiviral agents offers a beacon of hope. Nonetheless, the variant's adeptness at eluding the immunoprotective effects conferred by extant vaccines highlights the imperative for the development of more effective vaccines and therapeutic approaches. Overall, the distinct evolutionary trajectories of BA.2.86 and JN.1 underscore the necessity for ongoing surveillance and scholarly inquiry to elucidate their implications for the pandemic's evolution, which requires the international communities to foster collaboration through the sharing of data, exchange of insights, and collective scientific endeavors.

Aptamers targeting SARS-CoV-2 nucleocapsid protein exhibit potential anti pan-coronavirus activity.

Emerging and recurrent infectious diseases caused by human coronaviruses (HCoVs) continue to pose a significant threat to global public health security. In light of this ongoing threat, the development of a broad-spectrum drug to combat HCoVs is an urgently priority. Herein, we report a series of anti-pan-coronavirus ssDNA aptamers screened using Systematic Evolution of Ligands by Exponential Enrichment (SELEX). These aptamers have nanomolar affinity with the nucleocapsid protein (NP) of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and also show excellent binding efficiency to the N proteins of both SARS, MERS, HCoV-OC43 and -NL63 with affinity KD values of 1.31 to 135.36 nM. Such aptamer-based therapeutics exhibited potent antiviral activity against both the authentic SARS-CoV-2 prototype strain and the Omicron variant (BA.5) with EC50 values at 2.00 nM and 41.08 nM, respectively. The protein docking analysis also evidenced that these aptamers exhibit strong affinities for N proteins of pan-coronavirus and other HCoVs (-229E and -HKU1). In conclusion, we have identified six aptamers with a high pan-coronavirus antiviral activity, which could potentially serve as an effective strategy for preventing infections by unknown coronaviruses and addressing the ongoing global health threat.

Effect of second booster vaccination on clinical outcomes of Omicron-variant breakthrough infection: A propensity score matching cohort study.

Objective: To further explore the effect of vaccination regimen and frequency on clinical outcomes of breakthrough infections caused by the Omicron variant, as well as the durability of vaccine effectiveness. Methods: A retrospective, propensity score matching, real-world cohort study was conducted. Vaccination frequency was categorized into regular vaccination, first booster, and second booster. Results: A total of 7428 cases were included, with 3910 (53 %) being male. The median age was 39 years. BA.2 than BA.5/5.2 infection presented with more pulmonary symptoms and fewer influenza-like symptoms. Among the 3516 cases of BA.5/5.2 breakthrough infections, patients who received the second booster than the first booster or regular vaccination had higher first IgM and IgG titers and first cycle thredhold values for N gene on admission, a lower percentage of fever, lower peak body temperatures, and a higher percentage of asymptomatic cases. Patients who received the first booster vaccinated with homologous mRNA or heterologous inactivated plus mRNA vaccines than homologous inactivated vaccines had higher first IgM and IgG titers, a higher percentage of asymptomatic cases, and a lower percentage of fever. Moreover, significantly different first IgG titers were observed among patients receiving the second booster vaccinated with any of the three regimens. There was no statistical difference between booster regimens of homologous mRNA vaccines and heterologous inactivated plus mRNA vaccines. Patients in Month 7- than Month 0-6 after the first booster had lower first IgM and IgG titers and first cycle thredhold values, a lower percentage of asymptomatic cases, and a higher percentage of fever; and a higher percentage of pneumonia after the second booster. Conclusions: Repeated booster vaccinations every six months, with priority given to heterologous mRNA vaccine booster regimens in countries previously primarily using inactivated vaccines, may provide protection for adult patients with Omicron-variant breakthrough infections and improve clinical outcomes.

Development of a quadruple qRT-PCR assay for simultaneous identification of hypervirulent and carbapenem-resistant Klebsiella pneumoniae.

IMPORTANCE: Globally, the increasing number of hypervirulent Klebsiella pneumoniae (hvKp) and carbapenem-resistant Kp (CR-Kp) infections poses a huge public health challenge with high morbidity and mortality. Worrisomely, due to the mobility of elements carrying virulence and drug-resistance genes, the increasing prevalence of CR-hvKp has also been found with an overwhelming mortality rate in recent years. However, the current detection methods for hvKp and CR-Kp have many disadvantages, such as long turnaround time, complex operation, low sensitivity, and specificity. Herein, a more sensitive, rapid, single-reaction, and multiplex quantitative real-time PCR was developed and validated to differentiate the circulating lineages of Kp with excellent performance in sensitivity and specificity, providing a useful tool for the differential diagnosis and the surveillance of the circulating Kp.

Biotemplated precise assembly approach toward ultra-scaled high-performance electronics.

Structural DNA nanotechnology can be programmed into complex designer structures with molecular precision for directing a wide range of inorganic and biological materials. However, the use of DNA-templated approaches for the fabrication and performance requirements of ultra-scaled semiconductor electronics is limited by its assembly disorder and destructive interface composition. In this protocol, using carbon nanotubes (CNTs) as model semiconductors, we provide a stepwise process to build ultra-scaled, high-performance field-effect transistors (FETs) from micron-scale three-dimensional DNA templates. We apply the approach to assemble CNT arrays with uniform pitches scaled between 24.1 and 10.4 nm with yields of more than 95%, which exceeds the resolution limits of conventional lithography. To achieve highly clean CNT interfaces, we detail a rinsing-after-fixing step to remove residual DNA template and salt contaminations present around the contact and the channel regions, without modifying the alignment of the CNT arrays. The DNA-templated CNT FETs display both high on-state current (4-15 µA per CNT) and small subthreshold swing (60-100 mV per decade), which are superior to previous examples of biotemplated electronics and match the performance metrics of high-performance, silicon-based electronics. The scalable assembly of defect-free three-dimensional DNA templates requires 1 week and the CNT arrays can be synthesized within half a day. The interface engineering requires 1-2 d, while the fabrication of high-performance FET and logic gate circuits requires 2-4 d. The structural and performance characterizations of molecular-precise DNA self-assembly and high-performance electronics requires 1-2 d. The protocol is suited for users with expertise in DNA nanotechnology and semiconductor electronics.

Interactive effect of booster vaccination and vitamin D status on antibody production of Omicron variant-infected adults: A real-world cohort study.

INTRODUCTION: Effect of booster vaccination and vitamin D status on antibody production of Omicron variant-infected adults need to be further explored. METHODS: A retrospective, longitudinal, real-world cohort study was performed. All included cases were divided into vitamin D deficiency (VDD) and non-VDD (control) groups according to baseline serum 25-hydroxyvitamin D [25(OH)D] concentration and then into unvaccinated, routinely vaccinated, and booster vaccinated VDD and control subgroups according to vaccination status. Antibody dynamics were observed within six time periods during hospitalization. RESULTS: A total of 204 adult cases were included, of which 121 (59%) were males; 23 (11%), 31 (15%), and 26 (13%) or 50 (25%), 35 (17%), and 39 (19%) were unvaccinated, routinely vaccinated, and booster vaccinated VDD cases or controls, respectively. The median (interquartile range) for age and baseline 25(OH)D concentration was 42.5 (31-53.5) years and 21.5 (18-25.4) ng/mL, respectively. The IgM titers within 3 to 7 days and 7 to 14 days increased rapidly to 1.8-fold (P < 0.001) and 3.6-fold (P < 0.001) those within the first day; the IgG titers increased to 5.8-fold (P < 0.001) and 10.9-fold (P < 0.001). Booster vaccinated controls had higher first IgG titers compared with unvaccinated controls (3.1-fold; P = 0.001) or booster vaccinated VDD cases (2.1-fold; P = 0.02). CONCLUSIONS: Booster vaccination and non-VDD status may have an interactive boosting effect on IgG production of Omicron variant-infected adults. Further randomized clinical trials may be needed to determine whether booster vaccination combined with VDD correction improves the humoral immunity to Omicron variants.

Stabilizing the Deep Sodiation Process in Layered Sodium Manganese Cathodes by Anchoring Boron Ions.

Advanced high-energy-density sodium-ion batteries (SIBs) are inseparable from cathode materials with high specific capacities. Layered manganese-rich oxides (Nax MnO2 , 0.6 ≤ x ≤1) are promising cathode materials owing to their ease of intercalation and extraction of a considerable amount of sodium ions. However, lattice interactions, especially electrostatic repulsive forces and anisotropic stresses, are usually caused by deep desodiatin/sodiation process, resulting in intragranular cracks and capacity degradation in SIBs. Here, boron ions are introduced into the layered structure to build up B─O─Mn bonds. The regulated electronic structure in Na0.637 B0.038 MnO2 (B-NMO) materials inhibits the deformation of MnO6 octahedra, which finally achieves a gentle structural transition during the deep sodiation process. B-NMO electrode exhibits a high capacity (141 mAh g-1 ) at 1 C with a capacity retention of 81% after 100 cycles. Therefore, anchoring boron to manganese-rich materials inhibits the detrimental structural evolution of deep sodiation and can be used to obtain excellent cathode materials for SIBs.

Clinical features and transmission risk analysis of dengue virus infections in Shenzhen, During 2014-2019.

Dengue fever (DF) and dengue hemorrhagic fever (DHF) are among the most common tropical diseases affecting humans. To analyze the risk of clinical and transmission of DF/DHF in Shenzhen, the surveillance on patients of all-age patients with dengue virus (DENV) infections was conducted. Our findings revealed that the majority of DENV-infected patients are young to middle-aged males, and the development of the disease is accompanied by abnormal changes in the percentages of neutrophils, lymphocytes, and basophils. Demographic analysis revealed that these patients is concentrated in areas such as Futian District, which may be due to the higher mosquito density and temperature than that in other area. Subsequent, mosquito infection experiments confirmed that the effect of temperature shift on DENV proliferation and transmission. Not only that, constant temperatures can enhance the spread of DENV, even increase the risk of epidemic. Thus, the role of innate immune response should be highlighted in the prediction of severe severity of DENV-infected patients, and temperature should be taken into account in the prevention and control of DENV. Introduction: Dengue fever (DF) and dengue hemorrhagic fever (DHF) are among the most common tropical diseases affecting humans, and which caused by the four dengue virus serotypes (DENV 1-4). Objectives: To analyze the risk of clinical and transmission of DF/DHF in Shenzhen. Methods: The surveillance on patients of all-age patients with dengue virus (DENV) infections was conducted. Results: Our findings revealed that the majority of DENV-infected patients are young to middle-aged males, and the development of the disease is accompanied by abnormal changes in the percentages of neutrophils, lymphocytes, and basophils. Demographic analysis revealed that these patients is concentrated in areas such as Futian District, which may be due to the higher mosquito density and temperature than that in other area. Subsequent, mosquito infection experiments confirmed that the effect of temperature shift on DENV proliferation and transmission. Not only that, constant temperatures can enhance the spread of DENV, even increase the risk of epidemic. Conclusion: 1. Elevated levels of neutrophils, lymphocytes, basophils, and temperature are all significant risk factors for dengue transmission and pathogenesis; 2. Temperature increasing is associated with a higher risk of dengue transmission; 3. Fluctuations in temperature around 28 °C (28 ± 5 °C) would increase dengue transmission.

Intermittent hypoxia protects against hypoxic-ischemic brain damage by inducing functional angiogenesis.

Ischemic stroke (IS) induces neurological damage due to cerebrovascular occlusion. Restoring blood perfusion to the ischemic brain area in a timely fashion is the most effective treatment strategy. Hypoxia is an effective way of restoring blood perfusion by improving cerebrovascular microcirculation, while the effect varies greatly depending on hypoxic mode. This study aimed to screen for the optimal hypoxic mode to improve cerebrovascular microcirculation and prevent IS. Here, we found that compared with continuous hypoxia (CH), intermittent hypoxia (IH) significantly improved cerebral blood flow and oxygen saturation in mice without causing neurological impairment. By analyzing cerebrovascular microcirculation from mice, we found that the IH mode (13%, 5*10) with 13% O2, 5 min interval, and 10 cycles per day significantly improved the cerebrovascular microcirculation by promoting angiogenesis without affecting the integrity of the blood-brain barrier. In addition, IH (13%, 5*10) treatment of distal middle cerebral artery occlusion (dMCAO) mice significantly alleviated neurological dysfunction and reduced cerebral infarct volume by improving cerebrovascular microcirculation. CH had none of these positive effects. In summary, our study screened for an appropriate intermittent hypoxic mode that could improve cerebrovascular microcirculation, laying a theoretical foundation for the prevention and treatment of IS in clinical practice.

Factors associated with persistent positive in HBV DNA level in patients with chronic Hepatitis B receiving entecavir treatment.

Introduction: The clinical significance of persistent positive in Hepatitis B Virus (HBV) DNA level in patients receiving antiviral therapy is not well known. We investigated factors associated with persistent viremia (PV) in patients with chronic hepatitis B (CHB) given 78-week entecavir. Methods: A total of 394 treatment-naïve CHB patients who had undergone liver biopsy at baseline and week 78 of treatment were analyzed in this prospective multicentre study. We identified patients with PV (above the lower limit of quantification, 20 IU/ml) after 78 weeks of entecavir therapy. Stepwise, forward, multivariate regression analyses of specified baseline parameters were apllied to identify factors associated with PV. Futhermore, we assessed the incidence of hepatocellular carcinoma (HCC) in all patients using models of the risk of HCC development. Results: Of the 394 patients, 90 (22.8%) still with PV after 78-week antiviral treatment. Factors associated significantly with PV (vs complete virological response, CVR) were HBV DNA level ≥8 log10 IU/mL (OR, 3.727; 95% CI, 1.851-7.505; P < 0.001), Anti-HBc level < 3 log10 IU/mL (OR, 2.384; 95% CI, 1.223-4.645; P=0.011), and HBeAg seropositivity (OR, 2.871; 95% CI, 1.563-5.272; P < 0.001). Patients with PV were less likely to have fibrosis progression and HCC development than those with the CVR. Of the 11 HBeAg-positive patients with HBV DNA level ≥8 log10 IU/mL and Anti-HBc level < 3 log10 IU/mL at baseline, 9 (81.8%) had persistent positivity in HBV DNA level and 0 had fibrosis progression at week 78 of treatment. Discussion: In conclusion, HBV DNA level ≥8 log10 IU/mL, Anti-HBc level < 3 log10 IU/mL and HBeAg seropositivity at baseline contribute to PV in patients with CHB receiving 78-week antiviral treatment. In addition, the rate of fibrosis progression and the risk of HCC development in patients with PV were kept low. The complete protocol for the clinical trial has been registered at clinicaltrials.gov (NCT01962155 and NCT03568578).